Electromagnetic apparatus



Mar. 27, 1923- 1,449,852

c. A. cADwl-:LL

ELECTROMAGNETIC APPARATUS Original Filed Nov. 25,

1916 z sheets-sheet l TTOEJYE Y6.

Mar. 2 7, 1923- c. A. cADwELL ELECTROMAGNETIC APPARATUS Original Filed Nov. 25, 1916 2 sheets-sheet 2 Jay Patented Mar. 27, 1923.

UNITED STATES PATENT OFFICE.

CHARLES A. CADWELL, OF CLEVELAND, OHIO, ASSIGNOR TO THE ELECTRIC RAILWAY IMPROVEMENT COMPANY, OF CLEVELAND, OHIO, A CORPORATION OF OHIO.

ELECTROMAGNETIC APPARATUS.

Original application led November 25, 1916, Serial No. 133,347. Renewed .Tune 17, 1918, Serial No.

To all whom t may concern Be it known that I, CHARLES A. Cnownnr., a citizen of the United States, and a resident of Cleveland, county of Cuyahoga, and State of Chio, have invented a new and useful Improvement in Electromagnetic Apparatus, of which the following is a specification, the principle of the invention being herein explained and the best mode in which I have contemplated applying that principle, so as to distinguish it from other inventions.

My improved electro-magnetic apparatus is primarily designed for use in connection with an electric welding apparatus which forms the subject matter of my co-pending application filed November' 25, 1916, Serial No. 133,347, (since issued into Patent No. 1,290,903, dated January 14., 1919), out of which the present application has been required to be divided. The object of such electro-magnetic apparatus, accordingly, in the specific connection just referred to, is in the general applications to which it is equally adaptable, and to regulate and control the heating effect of an electric arc, so as to affect uniformly a considerably area. Such object may be more broadly stated still as being the production ofy a magnetic field of unique character, one electric use of which is found in its effect on an electric arc, as just stated. To the accomplishment of theforegoing and related ends, the invention, then, consists of the means hereinafter fully described and particularly pointed out in the claims, the annexed drawings and the following description setting forth in detail certain mechanism embodying the invention, which, however, constitutes but one of the various ways in which the principle of the invention may be used.

In said annexed drawings Fig. 1 is a` vertical longitudinal section of my improved electro-magnetic apparatus; Fig. 2 is a horizontal section of the same, the plane of the section being indicated by the line 2, 2, Fig. 1; Fig. 3 is a front elevational view of the apparatus; Fig. 1 is a transverse section of a portion of the apparatus, as indicated by the line 4, 4, Figs. 1 and 2; Fig. 5 is another section taken on the plane indicated by the line 5, 5, Figs. 1 and 3; and Fig. 6 is a diagrammatic illus- Patent No. 1,290,903. Divided and this application filed February 21, 1918.

Serial No.

tration of the apparatus, showing the circuit connection therefor.

As previously indicated, my improved electro-magnetic apparatus has been primarily designed for use in connection with a welding apparatus on the associated parts appearing in the several figures of the aforesaid drawings, pertaining to which a welding apparatus, specifically a welding apparatus for welding, brazing, or otherwise homogeneously uniting rail bonds onto rails. It will be found more desirable, in order to make clear the operative effect of the electro-magnetic apparatus proper to include a description of such associated parts. The main structural element in the heatmg device proper is a hollow metal core 1 preferably made out of wrought-iron and of the oblong rectangular form in cross-section shown in Fig. 3. As indicated in Figs. a and 5, such core is cut away or formed with longitudinal recesses 1a at its respective corners, so as to separate the top, bottom and sides from each other save near their respective front and rear ends. Surrounding such core 1 is a coil 2 consisting of a heavy conductor wound in the form of a helix, or rather two superimposed helices in the speciic embodiment illustrated, such coil preferably extending from near the front end of the core to a point a trifle short of its rear end. F langes 3 of non-conducting, heat-resisting material, such as asbestos board, bound the ends of the coil, which is further enclosed in a protective shell or casing 4, which may be of similar material, as shown in Figures, l and 2, or may be a perforated metal shell in order to give ventilation.

Attached by means of set screws or the like to opposite sides of core 1 at its rear end are two similar angular arms 5 of soft iron, the lateral portions of which are disposed alongside of the coil 2 and approximately parallel therewith, extending some distance forwardly of the device as a whole. The extreme inner ends ofthe rear portions of such arms which are thus attached to the core are similarly attached to and serve to support an inner metal core 6 of the same material as the outer one, which is spaced a slight distance from the latter and terminates some distance short of the front end thereof. To all intents and purposes, so far as operation is concerned, it will be under stood that the two cores land 6, with the aforesaid arms 5, are an integral structure. lying in the magnetic circuit of the coil and influencing the effect of the latter on the arc, which constitutes the source of heat in a fashion which will be more fully described later.

One of the members "between which such arc is established is an electrode consisting ot'- a rod or bar 10 of graphite that is slid ably supported in the inner core 6 by means of blocks 11 of asbestos composition, or similar non-conducting,heat-resisting material. The

coil 2 is preferably included in series with such electrode, the arrangement of the circuit being diagrammatically shown in Fig. 6, where the return, it will be observed, is through the rail 12 to the generator 13, which is illustrated as D. C. type. A suitable switch 14 will of course be included in the circuit at a point convenient to the appa ratus, as also a resistance 15 of any suitable construction, whereby the voltage may be brought down and regulated as desired, the apparatus being designed to take from onefourth to one-third of the voltage received from the service line. The electrode will also be provided at its rear end with a suitable handle (not shown), whereby it may be advanced or retracted as occasion may demand.

The forward endv of such electrode eX- tends through an aperture 20 in the rear wall of a heat-conserving or furnace chamber 21, separate from'the apparatus thus far described, the rear wall of such chamber consisting of a block of magnesiteor the like, while the front wall consists of a graphite block or plate 22, that is adapted to press against the article (e. g. the bond 23) to b'e welded, or heated for any other purpose, and constitutes at the same time the member between which and such electrode 10, the arc is formed. Further details of the construction of this furnace chamber 21 are not of interest in the present connec tion, and, in fact, reference to the graphite block or plate 22 is only necessary as an illustration of one of the results that may be obtained by the particular magnetic iield produced by my improved electro-magnetic apparatus. By reason of the unique construction of the above described electro-magnetic apparatus, including not merely two cores, one within the other, the inner core being shorter lthan the outer one, but also the angular hars 5 connecting the rear ends of such cores and lying alongside the coil 2 after the fashion of the arms of a magnet, a magnetic field is established, when a current is passed through the coil, that serves to direct and control the arc so as to steady the same and insure a.. uniform heating of the entire front face of the graphite block. Such arc is spread mostly in a horizontal direction, correspond-l ing with the longer diameter of the device, and so distributes the heat lengthwise of the bond terminal, which is usually of elongated form, and fuses the latter throughout its entire course. In the securing of this result, the slotting of the core 1 in a longitudinal direction at a plurality of. symmetrically related points about its periphery, as well as the separate character of the arms 5 and their separate attachment to the dual tubular core, has been found in practice to produce a much more satisfactory result in the pan ticular stated than any other form of apparatus with which I am acquainted. The study and analysis of magnetic fields is admittedly involved and ditcult, and theeffect of this particular construction on the field produced in the present instance is not capable of satisfactory theoretical explanation, or at least I am not certain as to such explanation. The fact as to the novel and useful effect produced nevertheless remains as stated.

Other modes of applying the principle of my invention may be employed instead of the one explained, change being made as regards the mechanism herein disclosed, provided the means stated by any of the following claims or the equivalent of such stated means be employed.

I therefore particularly point out and distinctly claim as my invention 1. An electro-magnetic coil, in combination with two tubular cores within such coil; and two angular arms connected with adj acent ends of said cores and lying alongside of said coil.

2. An electro-magnetic coil, in combination with two tubular cores within such coil, one lying within and spaced from the other; and two angular arms connected with adj acent ends of said cores and lying alongside of said coil.

3. An electro-magnetic coil, in combination with a tubular core within said coil approximately co-eXtensive therewith; a second tubular core, lying within, spaced from, and terminating short of the front end of said first core; and two angular arms connected with the adjacent ends of said cores and lying alongside of said coil.

4. An electro-magnetic coil, in combination with a tubular core, said core being formed with a plurality of longitudinal slots extending from near one end to near the other.

5. An electromagnetic coil, in combination with a tubular core, said core being formed with a plurality of longitudinal slots spaced substantially equidistantly about said core and extending from near one end to near the other thereof.

6. An electro-magnetic coil, in combination with a tubular core, said core being of general rectangular form in cross-section and formed adjacent its respective corners with slots extending from near one end to near the other.

7. An electro-magnetic coil, in combination with a tubular core, said core being formed with a plurality of longitudinal slots extending from near one end to near the other; and two angular arms connected with one end of said core and lying alongside of said coil.

8. An electro-magnetic coil, in combination with a tubular core, said core being formed with a plurality of longitudinal slots spaced substantially equidistantly l about said core and extending from near one end to near the other thereof; and two angular arnis connected with one end of said core in symmetrical relation with such slots and lying alongside of said coil.

9. An electro-magnetic coil, in combination with two tubular cores within such coil, the core adjacent such coil being formed with longitudinal slots extending from near -one end to near the other.

10. An electro-magnetic coil, in combination with two tubular cores within such coil, the core adjacent Such coil being formed with longitudinal slots extending from near one end to near the other; and two angular arms connected with the adjacent ends of said cores and lying alongside of said coil.

11. An electro-magnetic coil, in combination with a tubular core within said coil approximately co-extensive therewith, said core being of general rectangular form in crosssection and formed adjacent its respective corners with slots extending from near one end to near the other; and a second tubular core lying within, spaced from, and terminating short of the front end of said irst core.

12. An electro-magnetic coil, in combination with a tubular core within said coil approximately co-extensive therewith, said core being of general rectangular form in cross-section and formed adjacent its respective corners with slots ending from-near one end to near -the other; a second tubular core lying within, spaced from, and terminating short of the front end of said first core; and two angular arnis connected with the adjacent ends of said cores and lying alongside 0f said coil.

Signed by me, this 16 day of February,

CHARLES A. CADVVELL. 

